After pleading from the uprising's leaders, Britain and France began drafting a U.N. resolution for a no-fly zone in Libya that could balance the scales.

President Barack Obama warned that the U.S. and its NATO allies are still considering military options to stop what he called "unacceptable" violence by Gadhafi's regime. NATO decided to boost flights of AWACs surveillance planes over Libya to 24 from 10 hours a day, said Ivo Daalder, U.S. ambassador to NATO.

"I want to send a very clear message to those who are around Colonel Gadhafi. It is their choice to make how they operate moving forward. And they will be held accountable for whatever violence continues to take place," Obama said during remarks in the Oval Office on Monday.

Libyan warplanes launched multiple airstrikes Monday on opposition fighters regrouping at the oil port of Ras Lanouf on the Mediterranean coast a day after they were driven back by a heavy government counteroffensive aimed at stopping the rebel drive toward Tripoli, Gadhafi's stronghold.

One strike hit near a gas station in Ras Lanouf, blasting two large craters in the road and wounding at least two people in a pickup truck.

The rebels oppose any Western ground troops deploying in Libya, but they're pressing for a no-fly zone to relieve them of the threat from the air.

The rebels can take on "the rockets and the tanks, but not Gadhafi's air force," said Ali Suleiman, a rebel fighter at Ras Lanouf.

"We don't want a foreign military intervention (on the ground), but we do want a no-fly zone. We are all waiting for one."

Arab Gulf countries joined the calls for a no-fly zone, with the foreign minister of the United Arab Emirates saying a conference of his country's neighbors that the U.N. Security Council should "shoulder its historical responsibility for protecting the Libyan people."

Still, Western military intervention does not seem imminent - and the warnings may be an attempt to intimidate Gadhafi with words before deeds.

British and French officials said that the no-fly resolution was being drawn up as a contingency and that it has not been decided whether to put it before the U.N. Security Council, where Russia holds veto power and has rejected such a move. Western officials have said a no-fly zone does not require a U.N. mandate, but they would prefer to have one.

In the battles over the weekend, Gahdafi's forces unleashed their strongest use of airpower yet in the nearly 3-week-old uprising. A powerful assault by warplanes, helicopter gunships and heavy barrages of artillery, rockets and tank fire drove the opposition forces out of the town of Bin Jawwad, 375 miles east of the capital.

The counteroffensive blunted what had been a steady advance by a force of 500 to 1,000 rebel fighters pushing down the coastal highway along the Mediterranean Sea west toward Tripoli.

The rebels were forced back to Ras Lanouf, about 40 miles to the east.

The past three days of fighting killed 30 rebels and wounded 169, said Dr. Gebril Hewadi, a physician at Al-Jalaa Hospital in Benghazi.

The rebels are now struggling to set up supply lines for weapons, ammunition and food, with many living off junk food, cookies and cans of tuna. They are waiting for rocket launchers, tanks and other heavy weapons to arrive with reinforcements from their headquarters in the eastern city of Benghazi.

The fighting also appears to have outright shut down oil operations at Ras Lanouf and the larger nearby oil port of Brega, which were already operating at minimal capacity.